src/kitemviews/kfileitemmodelrolesupdater.cpp

   1 /***************************************************************************
   2  *   Copyright (C) 2011 by Peter Penz <peter.penz19@gmail.com>             *
   3  *                                                                         *
   4  *   This program is free software; you can redistribute it and/or modify  *
   5  *   it under the terms of the GNU General Public License as published by  *
   6  *   the Free Software Foundation; either version 2 of the License, or     *
   7  *   (at your option) any later version.                                   *
   8  *                                                                         *
   9  *   This program is distributed in the hope that it will be useful,       *
  10  *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
  11  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
  12  *   GNU General Public License for more details.                          *
  13  *                                                                         *
  14  *   You should have received a copy of the GNU General Public License     *
  15  *   along with this program; if not, write to the                         *
  16  *   Free Software Foundation, Inc.,                                       *
  17  *   51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA            *
  18  ***************************************************************************/
  19
  20 #include "kfileitemmodelrolesupdater.h"
  21
  22 #include "kfileitemmodel.h"
  23
  24 #include <KConfig>
  25 #include <KConfigGroup>
  26 #include <KDebug>
  27 #include <KDirWatch>
  28 #include <KFileItem>
  29 #include <KGlobal>
  30 #include <KIO/JobUiDelegate>
  31 #include <KIO/PreviewJob>
  32
  33 #include "private/kpixmapmodifier.h"
  34
  35 #include <QApplication>
  36 #include <QPainter>
  37 #include <QPixmap>
  38 #include <QElapsedTimer>
  39 #include <QTimer>
  40
  41 #include <algorithm>
  42
  43 #ifdef HAVE_NEPOMUK
  44     #include "private/knepomukrolesprovider.h"
  45     #include <Nepomuk2/ResourceWatcher>
  46 #endif
  47
  48 // Required includes for subItemsCount():
  49 #ifdef Q_WS_WIN
  50     #include <QDir>
  51 #else
  52     #include <dirent.h>
  53     #include <QFile>
  54 #endif
  55
  56 // #define KFILEITEMMODELROLESUPDATER_DEBUG
  57
  58 namespace {
  59     // Maximum time in ms that the KFileItemModelRolesUpdater
  60     // may perform a blocking operation
  61     const int MaxBlockTimeout = 200;
  62
  63     // If the number of items is smaller than ResolveAllItemsLimit,
  64     // the roles of all items will be resolved.
  65     const int ResolveAllItemsLimit = 500;
  66
  67     // Not only the visible area, but up to ReadAheadPages before and after
  68     // this area will be resolved.
  69     const int ReadAheadPages = 5;
  70 }
  71
  72 KFileItemModelRolesUpdater::KFileItemModelRolesUpdater(KFileItemModel* model, QObject* parent) :
  73     QObject(parent),
  74     m_state(Idle),
  75     m_previewChangedDuringPausing(false),
  76     m_iconSizeChangedDuringPausing(false),
  77     m_rolesChangedDuringPausing(false),
  78     m_previewShown(false),
  79     m_enlargeSmallPreviews(true),
  80     m_clearPreviews(false),
  81     m_finishedItems(),
  82     m_model(model),
  83     m_iconSize(),
  84     m_firstVisibleIndex(0),
  85     m_lastVisibleIndex(-1),
  86     m_maximumVisibleItems(50),
  87     m_roles(),
  88     m_resolvableRoles(),
  89     m_enabledPlugins(),
  90     m_pendingSortRoleItems(),
  91     m_pendingSortRoleIndexes(),
  92     m_pendingIndexes(),
  93     m_pendingPreviewItems(),
  94     m_previewJob(),
  95     m_recentlyChangedItemsTimer(0),
  96     m_recentlyChangedItems(),
  97     m_changedItems(),
  98     m_dirWatcher(0),
  99     m_watchedDirs()
 100   #ifdef HAVE_NEPOMUK
 101   , m_nepomukResourceWatcher(0),
 102     m_nepomukUriItems()
 103   #endif
 104 {
 105     Q_ASSERT(model);
 106
 107     const KConfigGroup globalConfig(KGlobal::config(), "PreviewSettings");
 108     m_enabledPlugins = globalConfig.readEntry("Plugins", QStringList()
 109                                                          << "directorythumbnail"
 110                                                          << "imagethumbnail"
 111                                                          << "jpegthumbnail");
 112
 113     connect(m_model, SIGNAL(itemsInserted(KItemRangeList)),
 114             this,    SLOT(slotItemsInserted(KItemRangeList)));
 115     connect(m_model, SIGNAL(itemsRemoved(KItemRangeList)),
 116             this,    SLOT(slotItemsRemoved(KItemRangeList)));
 117     connect(m_model, SIGNAL(itemsChanged(KItemRangeList,QSet<QByteArray>)),
 118             this,    SLOT(slotItemsChanged(KItemRangeList,QSet<QByteArray>)));
 119     connect(m_model, SIGNAL(itemsMoved(KItemRange,QList<int>)),
 120             this,    SLOT(slotItemsMoved(KItemRange,QList<int>)));
 121     connect(m_model, SIGNAL(sortRoleChanged(QByteArray,QByteArray)),
 122             this,    SLOT(slotSortRoleChanged(QByteArray,QByteArray)));
 123
 124     // Use a timer to prevent that each call of slotItemsChanged() results in a synchronous
 125     // resolving of the roles. Postpone the resolving until no update has been done for 1 second.
 126     m_recentlyChangedItemsTimer = new QTimer(this);
 127     m_recentlyChangedItemsTimer->setInterval(1000);
 128     m_recentlyChangedItemsTimer->setSingleShot(true);
 129     connect(m_recentlyChangedItemsTimer, SIGNAL(timeout()), this, SLOT(resolveRecentlyChangedItems()));
 130
 131     m_resolvableRoles.insert("size");
 132     m_resolvableRoles.insert("type");
 133     m_resolvableRoles.insert("isExpandable");
 134 #ifdef HAVE_NEPOMUK
 135     m_resolvableRoles += KNepomukRolesProvider::instance().roles();
 136 #endif
 137
 138     // When folders are expandable or the item-count is shown for folders, it is necessary
 139     // to watch the number of items of the sub-folder to be able to react on changes.
 140     m_dirWatcher = new KDirWatch(this);
 141     connect(m_dirWatcher, SIGNAL(dirty(QString)), this, SLOT(slotDirWatchDirty(QString)));
 142 }
 143
 144 KFileItemModelRolesUpdater::~KFileItemModelRolesUpdater()
 145 {
 146     killPreviewJob();
 147 }
 148
 149 void KFileItemModelRolesUpdater::setIconSize(const QSize& size)
 150 {
 151     if (size != m_iconSize) {
 152         m_iconSize = size;
 153         if (m_state == Paused) {
 154             m_iconSizeChangedDuringPausing = true;
 155         } else if (m_previewShown) {
 156             // An icon size change requires the regenerating of
 157             // all previews
 158             m_finishedItems.clear();
 159             startUpdating();
 160         }
 161     }
 162 }
 163
 164 QSize KFileItemModelRolesUpdater::iconSize() const
 165 {
 166     return m_iconSize;
 167 }
 168
 169 void KFileItemModelRolesUpdater::setVisibleIndexRange(int index, int count)
 170 {
 171     if (index < 0) {
 172         index = 0;
 173     }
 174     if (count < 0) {
 175         count = 0;
 176     }
 177
 178     if (index == m_firstVisibleIndex && count == m_lastVisibleIndex - m_firstVisibleIndex + 1) {
 179         // The range has not been changed
 180         return;
 181     }
 182
 183     m_firstVisibleIndex = index;
 184     m_lastVisibleIndex = qMin(index + count - 1, m_model->count() - 1);
 185
 186     startUpdating();
 187 }
 188
 189 void KFileItemModelRolesUpdater::setMaximumVisibleItems(int count)
 190 {
 191     m_maximumVisibleItems = count;
 192 }
 193
 194 void KFileItemModelRolesUpdater::setPreviewsShown(bool show)
 195 {
 196     if (show == m_previewShown) {
 197         return;
 198     }
 199
 200     m_previewShown = show;
 201     if (!show) {
 202         m_clearPreviews = true;
 203     }
 204
 205     updateAllPreviews();
 206 }
 207
 208 bool KFileItemModelRolesUpdater::previewsShown() const
 209 {
 210     return m_previewShown;
 211 }
 212
 213 void KFileItemModelRolesUpdater::setEnlargeSmallPreviews(bool enlarge)
 214 {
 215     if (enlarge != m_enlargeSmallPreviews) {
 216         m_enlargeSmallPreviews = enlarge;
 217         if (m_previewShown) {
 218             updateAllPreviews();
 219         }
 220     }
 221 }
 222
 223 bool KFileItemModelRolesUpdater::enlargeSmallPreviews() const
 224 {
 225     return m_enlargeSmallPreviews;
 226 }
 227
 228 void KFileItemModelRolesUpdater::setEnabledPlugins(const QStringList& list)
 229 {
 230     if (m_enabledPlugins != list) {
 231         m_enabledPlugins = list;
 232         if (m_previewShown) {
 233             updateAllPreviews();
 234         }
 235     }
 236 }
 237
 238 void KFileItemModelRolesUpdater::setPaused(bool paused)
 239 {
 240     if (paused == (m_state == Paused)) {
 241         return;
 242     }
 243
 244     if (paused) {
 245         m_state = Paused;
 246         killPreviewJob();
 247     } else {
 248         const bool updatePreviews = (m_iconSizeChangedDuringPausing && m_previewShown) ||
 249                                     m_previewChangedDuringPausing;
 250         const bool resolveAll = updatePreviews || m_rolesChangedDuringPausing;
 251         if (resolveAll) {
 252             m_finishedItems.clear();
 253         }
 254
 255         m_iconSizeChangedDuringPausing = false;
 256         m_previewChangedDuringPausing = false;
 257         m_rolesChangedDuringPausing = false;
 258
 259         if (!m_pendingSortRoleItems.isEmpty()) {
 260             m_state = ResolvingSortRole;
 261             resolveNextSortRole();
 262         } else {
 263             m_state = Idle;
 264             startUpdating();
 265         }
 266     }
 267 }
 268
 269 void KFileItemModelRolesUpdater::setRoles(const QSet<QByteArray>& roles)
 270 {
 271     if (m_roles != roles) {
 272         m_roles = roles;
 273
 274 #ifdef HAVE_NEPOMUK
 275         // Check whether there is at least one role that must be resolved
 276         // with the help of Nepomuk. If this is the case, a (quite expensive)
 277         // resolving will be done in KFileItemModelRolesUpdater::rolesData() and
 278         // the role gets watched for changes.
 279         const KNepomukRolesProvider& rolesProvider = KNepomukRolesProvider::instance();
 280         bool hasNepomukRole = false;
 281         QSetIterator<QByteArray> it(roles);
 282         while (it.hasNext()) {
 283             const QByteArray& role = it.next();
 284             if (rolesProvider.roles().contains(role)) {
 285                 hasNepomukRole = true;
 286                 break;
 287             }
 288         }
 289
 290         if (hasNepomukRole && !m_nepomukResourceWatcher) {
 291             Q_ASSERT(m_nepomukUriItems.isEmpty());
 292
 293             m_nepomukResourceWatcher = new Nepomuk2::ResourceWatcher(this);
 294             connect(m_nepomukResourceWatcher, SIGNAL(propertyChanged(Nepomuk2::Resource,Nepomuk2::Types::Property,QVariantList,QVariantList)),
 295                     this, SLOT(applyChangedNepomukRoles(Nepomuk2::Resource)));
 296         } else if (!hasNepomukRole && m_nepomukResourceWatcher) {
 297             delete m_nepomukResourceWatcher;
 298             m_nepomukResourceWatcher = 0;
 299             m_nepomukUriItems.clear();
 300         }
 301 #endif
 302
 303         if (m_state == Paused) {
 304             m_rolesChangedDuringPausing = true;
 305         } else {
 306             startUpdating();
 307         }
 308     }
 309 }
 310
 311 QSet<QByteArray> KFileItemModelRolesUpdater::roles() const
 312 {
 313     return m_roles;
 314 }
 315
 316 bool KFileItemModelRolesUpdater::isPaused() const
 317 {
 318     return m_state == Paused;
 319 }
 320
 321 QStringList KFileItemModelRolesUpdater::enabledPlugins() const
 322 {
 323     return m_enabledPlugins;
 324 }
 325
 326 void KFileItemModelRolesUpdater::slotItemsInserted(const KItemRangeList& itemRanges)
 327 {
 328     QElapsedTimer timer;
 329     timer.start();
 330
 331     // Determine the sort role synchronously for as many items as possible.
 332     if (m_resolvableRoles.contains(m_model->sortRole())) {
 333         int insertedCount = 0;
 334         foreach (const KItemRange& range, itemRanges) {
 335             const int lastIndex = insertedCount + range.index + range.count - 1;
 336             for (int i = insertedCount + range.index; i <= lastIndex; ++i) {
 337                 if (timer.elapsed() < MaxBlockTimeout) {
 338                     applySortRole(i);
 339                 } else {
 340                     m_pendingSortRoleItems.insert(m_model->fileItem(i));
 341                 }
 342             }
 343             insertedCount += range.count;
 344         }
 345
 346         applySortProgressToModel();
 347
 348         // If there are still items whose sort role is unknown, return
 349         // and handle them asynchronously.
 350         if (!m_pendingSortRoleItems.isEmpty()) {
 351             if (m_state != ResolvingSortRole) {
 352                 // Trigger the asynchronous determination of the sort role.
 353                 killPreviewJob();
 354                 m_state = ResolvingSortRole;
 355                 resolveNextSortRole();
 356             }
 357             return;
 358         }
 359     }
 360
 361     startUpdating();
 362 }
 363
 364 void KFileItemModelRolesUpdater::slotItemsRemoved(const KItemRangeList& itemRanges)
 365 {
 366     Q_UNUSED(itemRanges);
 367
 368     const bool allItemsRemoved = (m_model->count() == 0);
 369
 370     if (!m_watchedDirs.isEmpty()) {
 371         // Don't let KDirWatch watch for removed items
 372         if (allItemsRemoved) {
 373             foreach (const QString& path, m_watchedDirs) {
 374                 m_dirWatcher->removeDir(path);
 375             }
 376             m_watchedDirs.clear();
 377         } else {
 378             QMutableSetIterator<QString> it(m_watchedDirs);
 379             while (it.hasNext()) {
 380                 const QString& path = it.next();
 381                 if (m_model->index(KUrl(path)) < 0) {
 382                     m_dirWatcher->removeDir(path);
 383                     it.remove();
 384                 }
 385             }
 386         }
 387     }
 388
 389 #ifdef HAVE_NEPOMUK
 390     if (m_nepomukResourceWatcher) {
 391         // Don't let the ResourceWatcher watch for removed items
 392         if (allItemsRemoved) {
 393             m_nepomukResourceWatcher->setResources(QList<Nepomuk2::Resource>());
 394             m_nepomukResourceWatcher->stop();
 395             m_nepomukUriItems.clear();
 396         } else {
 397             QList<Nepomuk2::Resource> newResources;
 398             const QList<Nepomuk2::Resource> oldResources = m_nepomukResourceWatcher->resources();
 399             foreach (const Nepomuk2::Resource& resource, oldResources) {
 400                 const QUrl uri = resource.uri();
 401                 const KUrl itemUrl = m_nepomukUriItems.value(uri);
 402                 if (m_model->index(itemUrl) >= 0) {
 403                     newResources.append(resource);
 404                 } else {
 405                     m_nepomukUriItems.remove(uri);
 406                 }
 407             }
 408             m_nepomukResourceWatcher->setResources(newResources);
 409             if (newResources.isEmpty()) {
 410                 Q_ASSERT(m_nepomukUriItems.isEmpty());
 411                 m_nepomukResourceWatcher->stop();
 412             }
 413         }
 414     }
 415 #endif
 416
 417     if (allItemsRemoved) {
 418         m_state = Idle;
 419
 420         m_finishedItems.clear();
 421         m_pendingSortRoleItems.clear();
 422         m_pendingSortRoleIndexes.clear();
 423         m_pendingIndexes.clear();
 424         m_pendingPreviewItems.clear();
 425         m_recentlyChangedItems.clear();
 426         m_recentlyChangedItemsTimer->stop();
 427         m_changedItems.clear();
 428
 429         killPreviewJob();
 430     } else {
 431         // Only remove the items from m_finishedItems. They will be removed
 432         // from the other sets later on.
 433         QSet<KFileItem>::iterator it = m_finishedItems.begin();
 434         while (it != m_finishedItems.end()) {
 435             if (m_model->index(*it) < 0) {
 436                 it = m_finishedItems.erase(it);
 437             } else {
 438                 ++it;
 439             }
 440         }
 441
 442         // The visible items might have changed.
 443         startUpdating();
 444     }
 445 }
 446
 447 void KFileItemModelRolesUpdater::slotItemsMoved(const KItemRange& itemRange, QList<int> movedToIndexes)
 448 {
 449     Q_UNUSED(itemRange);
 450     Q_UNUSED(movedToIndexes);
 451
 452     // The indexes of the items with missing sort role are not valid any more.
 453     m_pendingSortRoleIndexes.clear();
 454
 455     // The visible items might have changed.
 456     startUpdating();
 457 }
 458
 459 void KFileItemModelRolesUpdater::slotItemsChanged(const KItemRangeList& itemRanges,
 460                                                   const QSet<QByteArray>& roles)
 461 {
 462     Q_UNUSED(roles);
 463
 464     // Find out if slotItemsChanged() has been done recently. If that is the
 465     // case, resolving the roles is postponed until a timer has exceeded
 466     // to prevent expensive repeated updates if files are updated frequently.
 467     const bool itemsChangedRecently = m_recentlyChangedItemsTimer->isActive();
 468
 469     QSet<KFileItem>& targetSet = itemsChangedRecently ? m_recentlyChangedItems : m_changedItems;
 470
 471     foreach (const KItemRange& itemRange, itemRanges) {
 472         int index = itemRange.index;
 473         for (int count = itemRange.count; count > 0; --count) {
 474             const KFileItem item = m_model->fileItem(index);
 475             targetSet.insert(item);
 476             ++index;
 477         }
 478     }
 479
 480     m_recentlyChangedItemsTimer->start();
 481
 482     if (!itemsChangedRecently) {
 483         updateChangedItems();
 484     }
 485 }
 486
 487 void KFileItemModelRolesUpdater::slotSortRoleChanged(const QByteArray& current,
 488                                                      const QByteArray& previous)
 489 {
 490     Q_UNUSED(current);
 491     Q_UNUSED(previous);
 492
 493     if (m_resolvableRoles.contains(current)) {
 494         m_pendingSortRoleItems.clear();
 495         m_pendingSortRoleIndexes.clear();
 496         m_finishedItems.clear();
 497
 498         const int count = m_model->count();
 499         QElapsedTimer timer;
 500         timer.start();
 501
 502         // Determine the sort role synchronously for as many items as possible.
 503         for (int index = 0; index < count; ++index) {
 504             if (timer.elapsed() < MaxBlockTimeout) {
 505                 applySortRole(index);
 506             } else {
 507                 m_pendingSortRoleItems.insert(m_model->fileItem(index));
 508             }
 509         }
 510
 511         applySortProgressToModel();
 512
 513         if (!m_pendingSortRoleItems.isEmpty()) {
 514             // Trigger the asynchronous determination of the sort role.
 515             killPreviewJob();
 516             m_state = ResolvingSortRole;
 517             resolveNextSortRole();
 518         }
 519     } else {
 520         m_state = Idle;
 521         m_pendingSortRoleItems.clear();
 522         m_pendingSortRoleIndexes.clear();
 523         applySortProgressToModel();
 524     }
 525 }
 526
 527 void KFileItemModelRolesUpdater::slotGotPreview(const KFileItem& item, const QPixmap& pixmap)
 528 {
 529     if (m_state != PreviewJobRunning) {
 530         return;
 531     }
 532
 533     m_changedItems.remove(item);
 534
 535     const int index = m_model->index(item);
 536     if (index < 0) {
 537         return;
 538     }
 539
 540     QPixmap scaledPixmap = pixmap;
 541
 542     const QString mimeType = item.mimetype();
 543     const int slashIndex = mimeType.indexOf(QLatin1Char('/'));
 544     const QString mimeTypeGroup = mimeType.left(slashIndex);
 545     if (mimeTypeGroup == QLatin1String("image")) {
 546         if (m_enlargeSmallPreviews) {
 547             KPixmapModifier::applyFrame(scaledPixmap, m_iconSize);
 548         } else {
 549             // Assure that small previews don't get enlarged. Instead they
 550             // should be shown centered within the frame.
 551             const QSize contentSize = KPixmapModifier::sizeInsideFrame(m_iconSize);
 552             const bool enlargingRequired = scaledPixmap.width()  < contentSize.width() &&
 553                                            scaledPixmap.height() < contentSize.height();
 554             if (enlargingRequired) {
 555                 QSize frameSize = scaledPixmap.size();
 556                 frameSize.scale(m_iconSize, Qt::KeepAspectRatio);
 557
 558                 QPixmap largeFrame(frameSize);
 559                 largeFrame.fill(Qt::transparent);
 560
 561                 KPixmapModifier::applyFrame(largeFrame, frameSize);
 562
 563                 QPainter painter(&largeFrame);
 564                 painter.drawPixmap((largeFrame.width()  - scaledPixmap.width()) / 2,
 565                                    (largeFrame.height() - scaledPixmap.height()) / 2,
 566                                    scaledPixmap);
 567                 scaledPixmap = largeFrame;
 568             } else {
 569                 // The image must be shrinked as it is too large to fit into
 570                 // the available icon size
 571                 KPixmapModifier::applyFrame(scaledPixmap, m_iconSize);
 572             }
 573         }
 574     } else {
 575         KPixmapModifier::scale(scaledPixmap, m_iconSize);
 576     }
 577
 578     QHash<QByteArray, QVariant> data = rolesData(item);
 579     data.insert("iconPixmap", scaledPixmap);
 580
 581     disconnect(m_model, SIGNAL(itemsChanged(KItemRangeList,QSet<QByteArray>)),
 582                this,    SLOT(slotItemsChanged(KItemRangeList,QSet<QByteArray>)));
 583     m_model->setData(index, data);
 584     connect(m_model, SIGNAL(itemsChanged(KItemRangeList,QSet<QByteArray>)),
 585             this,    SLOT(slotItemsChanged(KItemRangeList,QSet<QByteArray>)));
 586
 587     m_finishedItems.insert(item);
 588 }
 589
 590 void KFileItemModelRolesUpdater::slotPreviewFailed(const KFileItem& item)
 591 {
 592     if (m_state != PreviewJobRunning) {
 593         return;
 594     }
 595
 596     m_changedItems.remove(item);
 597
 598     const int index = m_model->index(item);
 599     if (index >= 0) {
 600         QHash<QByteArray, QVariant> data;
 601         data.insert("iconPixmap", QPixmap());
 602
 603         disconnect(m_model, SIGNAL(itemsChanged(KItemRangeList,QSet<QByteArray>)),
 604                    this,    SLOT(slotItemsChanged(KItemRangeList,QSet<QByteArray>)));
 605         m_model->setData(index, data);
 606         connect(m_model, SIGNAL(itemsChanged(KItemRangeList,QSet<QByteArray>)),
 607                 this,    SLOT(slotItemsChanged(KItemRangeList,QSet<QByteArray>)));
 608
 609         applyResolvedRoles(item, ResolveAll);
 610         m_finishedItems.insert(item);
 611     }
 612 }
 613
 614 void KFileItemModelRolesUpdater::slotPreviewJobFinished()
 615 {
 616     m_previewJob = 0;
 617
 618     if (m_state != PreviewJobRunning) {
 619         return;
 620     }
 621
 622     m_state = Idle;
 623
 624     if (!m_pendingPreviewItems.isEmpty()) {
 625         startPreviewJob(m_pendingPreviewItems);
 626     } else {
 627         if (!m_changedItems.isEmpty()) {
 628             updateChangedItems();
 629         }
 630     }
 631 }
 632
 633 void KFileItemModelRolesUpdater::resolveNextSortRole()
 634 {
 635     if (m_state != ResolvingSortRole) {
 636         return;
 637     }
 638
 639     if (m_pendingSortRoleItems.count() != m_pendingSortRoleIndexes.count()) {
 640         // The indexes with missing sort role have to be updated.
 641         m_pendingSortRoleIndexes.clear();
 642         foreach (const KFileItem& item, m_pendingSortRoleItems) {
 643             const int index = m_model->index(item);
 644             if (index < 0) {
 645                 m_pendingSortRoleItems.remove(item);
 646             } else {
 647                 m_pendingSortRoleIndexes.append(index);
 648             }
 649         }
 650
 651         std::sort(m_pendingSortRoleIndexes.begin(), m_pendingSortRoleIndexes.end());
 652     }
 653
 654     // Try to update an item in the visible range.
 655     QList<int>::iterator it = std::lower_bound(m_pendingSortRoleIndexes.begin(),
 656                                                 m_pendingSortRoleIndexes.end(),
 657                                                 m_firstVisibleIndex);
 658
 659     // It seems that there is no such item. Start with the first item in the list.
 660     if (it == m_pendingSortRoleIndexes.end()) {
 661         it = m_pendingSortRoleIndexes.begin();
 662     }
 663
 664     while (it != m_pendingSortRoleIndexes.end()) {
 665         // TODO: Note that removing an index from the list m_pendingSortRoleIndexes
 666         // at a random position is O(N). We might need a better solution
 667         // to make sure that this does not harm the performance if
 668         // many items have to be sorted.
 669         const int index = *it;
 670         const KFileItem item = m_model->fileItem(index);
 671
 672         // Continue if the sort role has already been determined for the
 673         // item, and the item has not been changed recently.
 674         if (!m_changedItems.contains(item) && m_model->data(index).contains(m_model->sortRole())) {
 675             m_pendingSortRoleItems.remove(item);
 676             m_pendingSortRoleIndexes.erase(it);
 677
 678             // Check if we are at the end of the list (note that the list's end has changed).
 679             if (it != m_pendingSortRoleIndexes.end()) {
 680                 ++it;
 681             }
 682             continue;
 683         }
 684
 685         applySortRole(index);
 686         m_pendingSortRoleItems.remove(item);
 687         m_pendingSortRoleIndexes.erase(it);
 688         break;
 689     }
 690
 691     if (!m_pendingSortRoleItems.isEmpty()) {
 692         applySortProgressToModel();
 693         QTimer::singleShot(0, this, SLOT(resolveNextSortRole()));
 694     } else {
 695         m_state = Idle;
 696
 697         // Prevent that we try to update the items twice.
 698         disconnect(m_model, SIGNAL(itemsMoved(KItemRange,QList<int>)),
 699                    this,    SLOT(slotItemsMoved(KItemRange,QList<int>)));
 700         applySortProgressToModel();
 701         connect(m_model, SIGNAL(itemsMoved(KItemRange,QList<int>)),
 702                 this,    SLOT(slotItemsMoved(KItemRange,QList<int>)));
 703         startUpdating();
 704     }
 705 }
 706
 707 void KFileItemModelRolesUpdater::resolveNextPendingRoles()
 708 {
 709     if (m_state != ResolvingAllRoles && m_state != PreviewJobRunning) {
 710         return;
 711     }
 712
 713     while (!m_pendingIndexes.isEmpty()) {
 714         const int index = m_pendingIndexes.takeFirst();
 715         const KFileItem item = m_model->fileItem(index);
 716
 717         if (m_finishedItems.contains(item)) {
 718             continue;
 719         }
 720
 721         if (m_previewShown) {
 722             // Only determine the icon. The other roles are resolved when the preview is received.
 723             applyResolvedRoles(item, ResolveFast);
 724         } else {
 725             applyResolvedRoles(item, ResolveAll);
 726             m_finishedItems.insert(item);
 727             m_changedItems.remove(item);
 728         }
 729
 730         break;
 731     }
 732
 733     if (!m_pendingIndexes.isEmpty()) {
 734         QTimer::singleShot(0, this, SLOT(resolveNextPendingRoles()));
 735     } else if (m_state != PreviewJobRunning) {
 736         m_state = Idle;
 737
 738         if (m_clearPreviews) {
 739             // Only go through the list if there are items which might still have previews.
 740             if (m_finishedItems.count() != m_model->count()) {
 741                 QHash<QByteArray, QVariant> data;
 742                 data.insert("iconPixmap", QPixmap());
 743
 744                 disconnect(m_model, SIGNAL(itemsChanged(KItemRangeList,QSet<QByteArray>)),
 745                            this,    SLOT(slotItemsChanged(KItemRangeList,QSet<QByteArray>)));
 746                 for (int index = 0; index <= m_model->count(); ++index) {
 747                     if (m_model->data(index).contains("iconPixmap")) {
 748                         m_model->setData(index, data);
 749                     }
 750                 }
 751                 connect(m_model, SIGNAL(itemsChanged(KItemRangeList,QSet<QByteArray>)),
 752                         this,    SLOT(slotItemsChanged(KItemRangeList,QSet<QByteArray>)));
 753
 754             }
 755             m_clearPreviews = false;
 756         }
 757
 758         if (!m_changedItems.isEmpty()) {
 759             updateChangedItems();
 760         }
 761     }
 762 }
 763
 764 void KFileItemModelRolesUpdater::resolveRecentlyChangedItems()
 765 {
 766     m_changedItems += m_recentlyChangedItems;
 767     m_recentlyChangedItems.clear();
 768     updateChangedItems();
 769 }
 770
 771 void KFileItemModelRolesUpdater::applyChangedNepomukRoles(const Nepomuk2::Resource& resource)
 772 {
 773 #ifdef HAVE_NEPOMUK
 774     const KUrl itemUrl = m_nepomukUriItems.value(resource.uri());
 775     const KFileItem item = m_model->fileItem(itemUrl);
 776
 777     if (item.isNull()) {
 778         // itemUrl is not in the model anymore, probably because
 779         // the corresponding file has been deleted in the meantime.
 780         return;
 781     }
 782
 783     QHash<QByteArray, QVariant> data = rolesData(item);
 784
 785     const KNepomukRolesProvider& rolesProvider = KNepomukRolesProvider::instance();
 786     QHashIterator<QByteArray, QVariant> it(rolesProvider.roleValues(resource, m_roles));
 787     while (it.hasNext()) {
 788         it.next();
 789         data.insert(it.key(), it.value());
 790     }
 791
 792     disconnect(m_model, SIGNAL(itemsChanged(KItemRangeList,QSet<QByteArray>)),
 793                this,    SLOT(slotItemsChanged(KItemRangeList,QSet<QByteArray>)));
 794     const int index = m_model->index(item);
 795     m_model->setData(index, data);
 796     connect(m_model, SIGNAL(itemsChanged(KItemRangeList,QSet<QByteArray>)),
 797             this,    SLOT(slotItemsChanged(KItemRangeList,QSet<QByteArray>)));
 798 #else
 799 #ifndef Q_CC_MSVC
 800     Q_UNUSED(resource);
 801 #endif
 802 #endif
 803 }
 804
 805 void KFileItemModelRolesUpdater::slotDirWatchDirty(const QString& path)
 806 {
 807     const bool getSizeRole = m_roles.contains("size");
 808     const bool getIsExpandableRole = m_roles.contains("isExpandable");
 809
 810     if (getSizeRole || getIsExpandableRole) {
 811         const int index = m_model->index(KUrl(path));
 812         if (index >= 0) {
 813             if (!m_model->fileItem(index).isDir()) {
 814                 // If INotify is used, KDirWatch issues the dirty() signal
 815                 // also for changed files inside the directory, even if we
 816                 // don't enable this behavior explicitly (see bug 309740).
 817                 return;
 818             }
 819
 820             QHash<QByteArray, QVariant> data;
 821
 822             const int count = subItemsCount(path);
 823             if (getSizeRole) {
 824                 data.insert("size", count);
 825             }
 826             if (getIsExpandableRole) {
 827                 data.insert("isExpandable", count > 0);
 828             }
 829
 830             // Note that we do not block the itemsChanged signal here.
 831             // This ensures that a new preview will be generated.
 832             m_model->setData(index, data);
 833         }
 834     }
 835 }
 836
 837 void KFileItemModelRolesUpdater::startUpdating()
 838 {
 839     // Updating the items in and near the visible area makes sense only
 840     // if sorting is finished.
 841     if (m_state == ResolvingSortRole || m_state == Paused) {
 842         return;
 843     }
 844
 845     if (m_finishedItems.count() == m_model->count()) {
 846         // All roles have been resolved already.
 847         m_state = Idle;
 848         return;
 849     }
 850
 851     int lastVisibleIndex = m_lastVisibleIndex;
 852     if (lastVisibleIndex <= 0) {
 853         // Guess a reasonable value for the last visible index if the view
 854         // has not told us about the real value yet.
 855         lastVisibleIndex = qMin(m_firstVisibleIndex + m_maximumVisibleItems, m_model->count() - 1);
 856         if (lastVisibleIndex <= 0) {
 857             lastVisibleIndex = qMin(200, m_model->count() - 1);
 858         }
 859     }
 860
 861     // Terminate all updates that are currently active.
 862     killPreviewJob();
 863     m_pendingIndexes.clear();
 864
 865     QElapsedTimer timer;
 866     timer.start();
 867
 868     // Determine the icons for the visible items synchronously.
 869     int index;
 870     for (index = m_firstVisibleIndex; index <= lastVisibleIndex && timer.elapsed() < MaxBlockTimeout; ++index) {
 871         const KFileItem item = m_model->fileItem(index);
 872         applyResolvedRoles(item, ResolveFast);
 873     }
 874     const int firstIndexWithoutIcon = index;
 875
 876     // Start the preview job or the asynchronous resolving of all roles.
 877     QList<int> indexes = indexesToResolve();
 878
 879     if (m_previewShown) {
 880         KFileItemList itemsToResolve;
 881         foreach (int index, indexes) {
 882             const KFileItem item = m_model->fileItem(index);
 883             if (!m_finishedItems.contains(item)) {
 884                 itemsToResolve.append(m_model->fileItem(index));
 885
 886                 // Remember the items which have no icon yet. A fast
 887                 // asynchronous resolving will be done to make sure
 888                 // that icons are loaded as quickly as possible, i.e.,
 889                 // before the previews arrive.
 890                 if (index < m_firstVisibleIndex || index >= firstIndexWithoutIcon) {
 891                     m_pendingIndexes.append(index);
 892                 }
 893             }
 894         }
 895
 896         startPreviewJob(itemsToResolve);
 897
 898         // Determine the icons asynchronously as fast as possible.
 899         QTimer::singleShot(0, this, SLOT(resolveNextPendingRoles()));
 900     } else {
 901         m_pendingIndexes = indexes;
 902         // Trigger the asynchronous resolving of all roles.
 903         m_state = ResolvingAllRoles;
 904         QTimer::singleShot(0, this, SLOT(resolveNextPendingRoles()));
 905     }
 906 }
 907
 908 void KFileItemModelRolesUpdater::startPreviewJob(const KFileItemList items)
 909 {
 910     m_state = PreviewJobRunning;
 911
 912     if (items.isEmpty()) {
 913         QTimer::singleShot(0, this, SLOT(slotPreviewJobFinished()));
 914         return;
 915     }
 916
 917     // PreviewJob internally caches items always with the size of
 918     // 128 x 128 pixels or 256 x 256 pixels. A (slow) downscaling is done
 919     // by PreviewJob if a smaller size is requested. For images KFileItemModelRolesUpdater must
 920     // do a downscaling anyhow because of the frame, so in this case only the provided
 921     // cache sizes are requested.
 922     const QSize cacheSize = (m_iconSize.width() > 128) || (m_iconSize.height() > 128)
 923                              ? QSize(256, 256) : QSize(128, 128);
 924
 925     // KIO::filePreview() will request the MIME-type of all passed items, which (in the
 926     // worst case) might block the application for several seconds. To prevent such
 927     // a blocking, we only pass items with known mime type to the preview job
 928     // (if the icon has already been determined for an item in startUpdating()
 929     // or resolveNextPendingRoles(), the type is known).
 930     // This also prevents that repeated expensive mime type determinations are
 931     // triggered here if a huge folder is loaded, and startUpdating() is called
 932     // repeatedly.
 933     //
 934     // Note that we always pass at least one item to the preview job to prevent
 935     // that we get an endless startPreviewJob()/slotPreviewJobFinished() loop
 936     // if there are no items with known mime types yet for some reason.
 937     const int count = items.count();
 938     int previewJobItemCount = 1;
 939
 940     // TODO: This will start a job with one item only if this function is
 941     // called from slotPreviewJobFinished(), and resolveNextPendingRoles()
 942     // has not reached the items yet. This can happen if the previous preview
 943     // job has finished very fast because generating previews failed for all
 944     // items.
 945     //
 946     // Idea to improve this: if the mime type of the first item is unknown,
 947     // determine mime types synchronously for a while.
 948     while (previewJobItemCount < qMin(count, m_maximumVisibleItems) &&
 949            items.at(previewJobItemCount).isMimeTypeKnown()) {
 950         ++previewJobItemCount;
 951     }
 952
 953     KFileItemList itemSubSet;
 954     itemSubSet.reserve(previewJobItemCount);
 955     m_pendingPreviewItems.clear();
 956     m_pendingPreviewItems.reserve(count - previewJobItemCount);
 957
 958     for (int i = 0; i < previewJobItemCount; ++i) {
 959         itemSubSet.append(items.at(i));
 960     }
 961
 962     for (int i = previewJobItemCount; i < count; ++i) {
 963         m_pendingPreviewItems.append(items.at(i));
 964     }
 965
 966     KIO::PreviewJob* job = new KIO::PreviewJob(itemSubSet, cacheSize, &m_enabledPlugins);
 967
 968     job->setIgnoreMaximumSize(itemSubSet.first().isLocalFile());
 969     if (job->ui()) {
 970         job->ui()->setWindow(qApp->activeWindow());
 971     }
 972
 973     connect(job,  SIGNAL(gotPreview(KFileItem,QPixmap)),
 974             this, SLOT(slotGotPreview(KFileItem,QPixmap)));
 975     connect(job,  SIGNAL(failed(KFileItem)),
 976             this, SLOT(slotPreviewFailed(KFileItem)));
 977     connect(job,  SIGNAL(finished(KJob*)),
 978             this, SLOT(slotPreviewJobFinished()));
 979
 980     m_previewJob = job;
 981 }
 982
 983 void KFileItemModelRolesUpdater::updateChangedItems()
 984 {
 985     if (m_state == Paused) {
 986         return;
 987     }
 988
 989     if (m_changedItems.isEmpty()) {
 990         return;
 991     }
 992
 993     m_finishedItems -= m_changedItems;
 994
 995     if (m_resolvableRoles.contains(m_model->sortRole())) {
 996         m_pendingSortRoleItems += m_changedItems;
 997
 998         if (m_state != ResolvingSortRole) {
 999             // Stop the preview job if necessary, and trigger the
1000             // asynchronous determination of the sort role.
1001             killPreviewJob();
1002             m_state = ResolvingSortRole;
1003             QTimer::singleShot(0, this, SLOT(resolveNextSortRole()));
1004         }
1005
1006         return;
1007     }
1008
1009     QList<int> visibleChangedIndexes;
1010     QList<int> invisibleChangedIndexes;
1011
1012     foreach (const KFileItem& item, m_changedItems) {
1013         const int index = m_model->index(item);
1014
1015         if (index < 0) {
1016             m_changedItems.remove(item);
1017             continue;
1018         }
1019
1020         if (index >= m_firstVisibleIndex && index <= m_lastVisibleIndex) {
1021             visibleChangedIndexes.append(index);
1022         } else {
1023             invisibleChangedIndexes.append(index);
1024         }
1025     }
1026
1027     std::sort(visibleChangedIndexes.begin(), visibleChangedIndexes.end());
1028
1029     if (m_previewShown) {
1030         KFileItemList visibleChangedItems;
1031         KFileItemList invisibleChangedItems;
1032
1033         foreach (int index, visibleChangedIndexes) {
1034             visibleChangedItems.append(m_model->fileItem(index));
1035         }
1036
1037         foreach (int index, invisibleChangedIndexes) {
1038             invisibleChangedItems.append(m_model->fileItem(index));
1039         }
1040
1041         if (m_previewJob) {
1042             m_pendingPreviewItems += visibleChangedItems + invisibleChangedItems;
1043         } else {
1044             startPreviewJob(visibleChangedItems + invisibleChangedItems);
1045         }
1046     } else {
1047         const bool resolvingInProgress = !m_pendingIndexes.isEmpty();
1048         m_pendingIndexes = visibleChangedIndexes + m_pendingIndexes + invisibleChangedIndexes;
1049         if (!resolvingInProgress) {
1050             // Trigger the asynchronous resolving of the changed roles.
1051             m_state = ResolvingAllRoles;
1052             QTimer::singleShot(0, this, SLOT(resolveNextPendingRoles()));
1053         }
1054     }
1055 }
1056
1057 void KFileItemModelRolesUpdater::applySortRole(int index)
1058 {
1059     QHash<QByteArray, QVariant> data;
1060     const KFileItem item = m_model->fileItem(index);
1061
1062     if (index >= m_firstVisibleIndex && index <= m_lastVisibleIndex) {
1063         // Determine the icon.
1064         applyResolvedRoles(item, ResolveFast);
1065     }
1066
1067     if (m_model->sortRole() == "type") {
1068         if (!item.isMimeTypeKnown()) {
1069             item.determineMimeType();
1070         }
1071
1072         data.insert("type", item.mimeComment());
1073     } else if (m_model->sortRole() == "size" && item.isLocalFile() && item.isDir()) {
1074         const QString path = item.localPath();
1075         data.insert("size", subItemsCount(path));
1076     } else {
1077         // Probably the sort role is a Nepomuk role - just determine all roles.
1078         data = rolesData(item);
1079     }
1080
1081     disconnect(m_model, SIGNAL(itemsChanged(KItemRangeList,QSet<QByteArray>)),
1082                this,    SLOT(slotItemsChanged(KItemRangeList,QSet<QByteArray>)));
1083     m_model->setData(index, data);
1084     connect(m_model, SIGNAL(itemsChanged(KItemRangeList,QSet<QByteArray>)),
1085             this,    SLOT(slotItemsChanged(KItemRangeList,QSet<QByteArray>)));
1086 }
1087
1088 void KFileItemModelRolesUpdater::applySortProgressToModel()
1089 {
1090     // Inform the model about the progress of the resolved items,
1091     // so that it can give an indication when the sorting has been finished.
1092     const int resolvedCount = m_model->count() - m_pendingSortRoleItems.count();
1093     m_model->emitSortProgress(resolvedCount);
1094 }
1095
1096 bool KFileItemModelRolesUpdater::applyResolvedRoles(const KFileItem& item, ResolveHint hint)
1097 {
1098     if (item.isNull()) {
1099         return false;
1100     }
1101
1102     const bool resolveAll = (hint == ResolveAll);
1103
1104     bool iconChanged = false;
1105     if (!item.isMimeTypeKnown() || !item.isFinalIconKnown()) {
1106         item.determineMimeType();
1107         iconChanged = true;
1108     } else if (m_state == ResolvingSortRole || m_state == PreviewJobRunning) {
1109         // We are currently performing a fast determination of all icons
1110         // in the visible area.
1111         const int index = m_model->index(item);
1112         if (!m_model->data(index).contains("iconName")) {
1113             iconChanged = true;
1114         }
1115     }
1116
1117     if (iconChanged || resolveAll || m_clearPreviews) {
1118         const int index = m_model->index(item);
1119         if (index < 0) {
1120             return false;
1121         }
1122
1123         QHash<QByteArray, QVariant> data;
1124         if (resolveAll) {
1125             data = rolesData(item);
1126         }
1127
1128         data.insert("iconName", item.iconName());
1129
1130         if (m_clearPreviews) {
1131             data.insert("iconPixmap", QPixmap());
1132         }
1133
1134         disconnect(m_model, SIGNAL(itemsChanged(KItemRangeList,QSet<QByteArray>)),
1135                    this,    SLOT(slotItemsChanged(KItemRangeList,QSet<QByteArray>)));
1136         m_model->setData(index, data);
1137         connect(m_model, SIGNAL(itemsChanged(KItemRangeList,QSet<QByteArray>)),
1138                 this,    SLOT(slotItemsChanged(KItemRangeList,QSet<QByteArray>)));
1139         return true;
1140     }
1141
1142     return false;
1143 }
1144
1145 QHash<QByteArray, QVariant> KFileItemModelRolesUpdater::rolesData(const KFileItem& item) const
1146 {
1147     QHash<QByteArray, QVariant> data;
1148
1149     const bool getSizeRole = m_roles.contains("size");
1150     const bool getIsExpandableRole = m_roles.contains("isExpandable");
1151
1152     if ((getSizeRole || getIsExpandableRole) && item.isDir()) {
1153         if (item.isLocalFile()) {
1154             const QString path = item.localPath();
1155             const int count = subItemsCount(path);
1156             if (getSizeRole) {
1157                 data.insert("size", count);
1158             }
1159             if (getIsExpandableRole) {
1160                 data.insert("isExpandable", count > 0);
1161             }
1162
1163             if (!m_dirWatcher->contains(path)) {
1164                 m_dirWatcher->addDir(path);
1165                 m_watchedDirs.insert(path);
1166             }
1167         } else if (getSizeRole) {
1168             data.insert("size", -1); // -1 indicates an unknown number of items
1169         }
1170     }
1171
1172     if (m_roles.contains("type")) {
1173         data.insert("type", item.mimeComment());
1174     }
1175
1176     data.insert("iconOverlays", item.overlays());
1177
1178 #ifdef HAVE_NEPOMUK
1179     if (m_nepomukResourceWatcher) {
1180         const KNepomukRolesProvider& rolesProvider = KNepomukRolesProvider::instance();
1181         Nepomuk2::Resource resource(item.nepomukUri());
1182         QHashIterator<QByteArray, QVariant> it(rolesProvider.roleValues(resource, m_roles));
1183         while (it.hasNext()) {
1184             it.next();
1185             data.insert(it.key(), it.value());
1186         }
1187
1188         QUrl uri = resource.uri();
1189         if (uri.isEmpty()) {
1190             // TODO: Is there another way to explicitly create a resource?
1191             // We need a resource to be able to track it for changes.
1192             resource.setRating(0);
1193             uri = resource.uri();
1194         }
1195         if (!uri.isEmpty() && !m_nepomukUriItems.contains(uri)) {
1196             m_nepomukResourceWatcher->addResource(resource);
1197
1198             if (m_nepomukUriItems.isEmpty()) {
1199                 m_nepomukResourceWatcher->start();
1200             }
1201
1202             m_nepomukUriItems.insert(uri, item.url());
1203         }
1204     }
1205 #endif
1206
1207     return data;
1208 }
1209
1210 int KFileItemModelRolesUpdater::subItemsCount(const QString& path) const
1211 {
1212     const bool countHiddenFiles = m_model->showHiddenFiles();
1213     const bool showFoldersOnly  = m_model->showDirectoriesOnly();
1214
1215 #ifdef Q_WS_WIN
1216     QDir dir(path);
1217     QDir::Filters filters = QDir::NoDotAndDotDot | QDir::System;
1218     if (countHiddenFiles) {
1219         filters |= QDir::Hidden;
1220     }
1221     if (showFoldersOnly) {
1222         filters |= QDir::Dirs;
1223     } else {
1224         filters |= QDir::AllEntries;
1225     }
1226     return dir.entryList(filters).count();
1227 #else
1228     // Taken from kdelibs/kio/kio/kdirmodel.cpp
1229     // Copyright (C) 2006 David Faure <faure@kde.org>
1230
1231     int count = -1;
1232     DIR* dir = ::opendir(QFile::encodeName(path));
1233     if (dir) {  // krazy:exclude=syscalls
1234         count = 0;
1235         struct dirent *dirEntry = 0;
1236         while ((dirEntry = ::readdir(dir))) {
1237             if (dirEntry->d_name[0] == '.') {
1238                 if (dirEntry->d_name[1] == '\0' || !countHiddenFiles) {
1239                     // Skip "." or hidden files
1240                     continue;
1241                 }
1242                 if (dirEntry->d_name[1] == '.' && dirEntry->d_name[2] == '\0') {
1243                     // Skip ".."
1244                     continue;
1245                 }
1246             }
1247
1248             // If only directories are counted, consider an unknown file type and links also
1249             // as directory instead of trying to do an expensive stat()
1250             // (see bugs 292642 and 299997).
1251             const bool countEntry = !showFoldersOnly ||
1252                                     dirEntry->d_type == DT_DIR ||
1253                                     dirEntry->d_type == DT_LNK ||
1254                                     dirEntry->d_type == DT_UNKNOWN;
1255             if (countEntry) {
1256                 ++count;
1257             }
1258         }
1259         ::closedir(dir);
1260     }
1261     return count;
1262 #endif
1263 }
1264
1265 void KFileItemModelRolesUpdater::updateAllPreviews()
1266 {
1267     if (m_state == Paused) {
1268         m_previewChangedDuringPausing = true;
1269     } else {
1270         m_finishedItems.clear();
1271         startUpdating();
1272     }
1273 }
1274
1275 void KFileItemModelRolesUpdater::killPreviewJob()
1276 {
1277     if (m_previewJob) {
1278         disconnect(m_previewJob,  SIGNAL(gotPreview(KFileItem,QPixmap)),
1279                    this, SLOT(slotGotPreview(KFileItem,QPixmap)));
1280         disconnect(m_previewJob,  SIGNAL(failed(KFileItem)),
1281                    this, SLOT(slotPreviewFailed(KFileItem)));
1282         disconnect(m_previewJob,  SIGNAL(finished(KJob*)),
1283                    this, SLOT(slotPreviewJobFinished()));
1284         m_previewJob->kill();
1285         m_previewJob = 0;
1286         m_pendingPreviewItems.clear();
1287     }
1288 }
1289
1290 QList<int> KFileItemModelRolesUpdater::indexesToResolve() const
1291 {
1292     const int count = m_model->count();
1293
1294     QList<int> result;
1295     result.reserve(ResolveAllItemsLimit);
1296
1297     // Add visible items.
1298     for (int i = m_firstVisibleIndex; i <= m_lastVisibleIndex; ++i) {
1299         result.append(i);
1300     }
1301
1302     // We need a reasonable upper limit for number of items to resolve after
1303     // and before the visible range. m_maximumVisibleItems can be quite large
1304     // when using Compace View.
1305     const int readAheadItems = qMin(ReadAheadPages * m_maximumVisibleItems, ResolveAllItemsLimit / 2);
1306
1307     // Add items after the visible range.
1308     const int endExtendedVisibleRange = qMin(m_lastVisibleIndex + readAheadItems, count - 1);
1309     for (int i = m_lastVisibleIndex + 1; i <= endExtendedVisibleRange; ++i) {
1310         result.append(i);
1311     }
1312
1313     // Add items before the visible range in reverse order.
1314     const int beginExtendedVisibleRange = qMax(0, m_firstVisibleIndex - readAheadItems);
1315     for (int i = m_firstVisibleIndex - 1; i >= beginExtendedVisibleRange; --i) {
1316         result.append(i);
1317     }
1318
1319     // Add items on the last page.
1320     const int beginLastPage = qMax(qMin(endExtendedVisibleRange + 1, count - 1), count - m_maximumVisibleItems);
1321     for (int i = beginLastPage; i < count; ++i) {
1322         result.append(i);
1323     }
1324
1325     // Add items on the first page.
1326     const int endFirstPage = qMin(qMax(beginExtendedVisibleRange - 1, 0), m_maximumVisibleItems);
1327     for (int i = 0; i <= endFirstPage; ++i) {
1328         result.append(i);
1329     }
1330
1331     // Continue adding items until ResolveAllItemsLimit is reached.
1332     int remainingItems = ResolveAllItemsLimit - result.count();
1333
1334     for (int i = endExtendedVisibleRange + 1; i < beginLastPage && remainingItems > 0; ++i) {
1335         result.append(i);
1336         --remainingItems;
1337     }
1338
1339     for (int i = beginExtendedVisibleRange - 1; i > endFirstPage && remainingItems > 0; --i) {
1340         result.append(i);
1341         --remainingItems;
1342     }
1343
1344     return result;
1345 }
1346
1347 #include "kfileitemmodelrolesupdater.moc"